Carburetor Assembly – Fits Tohatsu/Mercury 15-20 HP 4-Stroke (Replaces 3BJ-03100-0)

Carburetor Assembly – Fits Tohatsu/Mercury 15-20 HP 4-Stroke (Replaces 3BJ-03100-0)

This aftermarket carburetor assembly is designed as a direct replacement for Tohatsu/Nissan 4-stroke 15-20 HP outboard engines, specifically fitting MFS20C models from 2008–2014. It is also compatible with equivalent Mercury 15-20 HP 4-stroke outboards and certain Johnson/Evinrude 20 HP models.

This unit directly replaces Tohatsu part number 3BJ-03100-0, Mercury part numbers 853720T21 / 8M0109535, and Johnson/Evinrude part number 5040597.

• Engineered for simple, direct OEM replacement installation.
• Includes necessary mounting gaskets for a complete seal.
• Compatible with standard gasoline fuel types.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below.

For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

For Johnson/Evinrude owners, here’s a guide to help you identify your engine’s serial/model: Johnson Serial Number Guide.

Technical Specifications

Package Contents

• 1 x Carburetor Assembly (3BJ-03100-0)

Installation Guide

Professional installation is recommended. Always refer to your engine’s official service manual for detailed procedures and safety warnings.

1. Ensure the engine is off and cool. Disconnect the battery and shut off the fuel supply.
2. Carefully note and detach the fuel lines, throttle linkages, and any electrical connectors from the old carburetor.
3. Remove the mounting bolts or nuts that secure the old carburetor to the intake manifold.
4. Gently remove the old carburetor and its gasket. Clean the manifold mounting surface thoroughly, ensuring it is free of old gasket material and debris.
5. Place the new gasket onto the manifold, followed by the new carburetor assembly.
6. Secure the new carburetor by tightening the mounting bolts evenly and to the manufacturer's specified torque.
7. Reconnect the fuel lines, throttle linkages, and any other connections. Ensure all are secure.
8. Turn the fuel supply back on and prime the system if necessary. Carefully check for any fuel leaks before proceeding.
9. Reconnect the battery, start the engine, and check for smooth idling and proper throttle response. Adjust idle speed if required.

Troubleshooting & FAQ

Q: How do I confirm this carburetor fits my engine?
A: The most reliable method is to match the part number from your original carburetor to one of the numbers listed in our Part Number Cross-Reference table. Additionally, check the Compatible Engine Models table to see if your specific engine model and year are listed.

Q: What are common signs that my old carburetor needs to be replaced?
A: Symptoms of a failing carburetor include difficulty starting, rough idling, stalling at low speeds, poor acceleration, excessive fuel consumption, or black smoke from the exhaust. Visible fuel leaks around the carburetor body are also a clear indicator.

Q: Does this assembly come with everything needed for installation?
A: This carburetor assembly includes the necessary mounting gaskets for a standard installation. However, you may need basic hand tools and your engine's service manual for guidance.

Q: What is the difference between an OEM and an aftermarket part?
A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?
A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?
A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.